Vinyl polymer with basic complex lead compound



United States Patent 3,312,647 VINYL POLYMER WITH BASIC COMPLEX LEADCOMPOUND Alfred Szczepanek and Margarete Szczepanek, nee

Schnoor, Niederan uber Duren, Rhineland, Germany, assignors to ChemischeFabrik Hoesch K.G., Duren, Germany, a company of Germany No Drawing.Filed Oct. 29, 1962, Ser. No. 233,898 Claims priority, applicationGermany, Dec. 22, 1955,

3 Claims. (Cl. 260-23) The present application is a continuation-in-partof copending application Ser. No. 629,461, filed December 20, 1956, andentitled, Basic Complex Lead Oompounds, now Patent No. 3,072,693.

The present invention relates to compositions containing complex leadcompounds as pigments and/or stabilizers especially for halogencontaining plastics, and to a process of making such compositions.

It is one object of the present invention to provide new and valuablecompositions which contain specific complex lead compounds which haveproved to be of value as pigments and/or as stabilizers forhalogencontaining plastics.

Another object of the present invention is to provide a simple andeifective process of preparing such new and valuable compositions.

Other objects of the present invention and advantage ous featuresthereof will become apparent as the invention proceeds.

In principle the new complex lead compound contained in suchcompositions according to the present invention correspond to thefollowing formula In said formula n indicates the numerals O to 16;

m indicates the numerals 0.5 to 4;

Ac indicates an inorganic dibasic acid residue, namely 804, CO3, and

Ac indicates an organic saturated or unsaturated monobasic aliphaticacid, residue such as stearic acid, lauric acid, ethyl hexanoic acid; asaturated or unsaturated dibasic aliphatic acid, such as adipic acid; amonobasic aromatic acid, such as benzoic acid or salicylic acid; or adibasic aromatic acid such as phthalic acid; and

x indicates the numeral 1 when Ae is a dibasic acid and the numeral 2when A0 is a monobasic acid.

Such basic complex lead salts are prdouced according to said copendingapplication Ser. No. 629,461 by reacting basic inorganic lead salts withorganic acids to form complex compounds. Especially suitable inorganiclead salts are tetrabasic lead sulfate, basic lead carbonate, anddibasic lead phosphite. Suitable organic acids used for this reactionare saturated and unsaturated mo-noand dicarboxylic acids of thealiphatic and aromatic series such as, for instance, stearic acid, oleicacid, linoleic acid, maleic acid, a-ethyl hexanoic acid, adipic acid,benzoic acid, phthalic acid, lauric acid, fatty acids obtained onsplitting coconut oil, ricinoleic acid, and the like. Such organic acidsare used for the reaction With basic inorganic lead salts, either assuch, or in mixture with each other. The reaction products withsaturated and unsaturated fatty acid represent especially valuablestabilizers for processing polyvinyl chloride plastics because theyimpart to the basic inorganic lead compounds excellent sliding andlubricating properties.

Said process may be modified by causing the resulting basic complex leadcompounds to react with additional amount of lead oxide. A a resultthereof the heat- 3,312,64l Patented Apr. 4, 1967 stabilizing leadcontent of the complex compound is increased. The above characterizedcomplex lead compounds can be produced according to the followingprincipal methods whereby the process may 'be carried out in thepresence or in the absence of a catalyst:

(a) Reaction of the inorganic lead salts with Waterinsoluble organicacid:

( 1) The organic acid is dispersed in flake form together with acatalyst in water at elevated temperature and the basic inorganic leadsalt is added portion by portion to the dispersion.

(2) The basic inorganic lead salt is dispersed in water together with acatalyst and the flaky organic acid is added thereto portion by portion.

(3) The 'basic inorganic lead salt is dispersed in Water and the moltenorganic acid is added to the dispersion while stirring.

(4) The basic inorganic lead salt and the pulverulent or flaky fattyacid are stirred without catalyst at elevated temperature for aprolonged period of time.

(5) Lead oxide and the inorganic acid are reacted to form the basic leadsalt and the organic acid and, if desired, a catalyst, are added to thereaction mixture.

(b) Reaction of the inorganic lead salts with watersoluble organicacids:

(1) An aqueous solution of the organic acid is added to a dispersion ofthe basic inorganic lead salt in water.

(2) The basic inorganic lead salt is dispersed in water, if desired,together with the catalyst and the organic acid is added to thedispersion.

(c) The basic lead salt is first produced and is subsequently reactedwith lead oxide with or without the addition of a catalyst and air ispassed through the reaction mixture in order to produce a white reactionproduct and to introduce the maximum amount of lead oxide.

It is also possible to produce normal as well as higher basic complexlead compounds by starting with the individual components of suchcomplex compounds, namely inorganic acid, lead oxide, and organic acid.It is, however, advisable to proceed in such a manner thatmicrocrystalline products are obtained, since the size of the surfacearea determines the usefulness of the basic complex compound as pigmentand stabilizer.

The reactants are reacted with each other in stoichiometrical amounts.Since in almost all instances the resulting reaction products areinsoluble, the yield is substantially quantitative. The reaction maybecarried out at room temperature or at elevated temperature. Elevatedtemperature accelerates the reaction. 'The upper temperature limit isgiven by the melting point of the organic acid if it is insoluble inwater. When using water-soluble acids, the temperature can be increasedto the boiling temperature of water.

The amount of water present in this reaction is adjusted in such amanner that the dispersion of the reactants can properly be stirred.Stirring should be as vigorous as possible in order to increase thespeed of reaction. Stirring devices of the grinding or crushing type arenot required.

Substances which cause wetting of the reactants are especially suitablecatalysts. Not only the known wetting agents but also organic compoundswhich have a low water-solubility exhibit such a wetting action and areuseful catalysts. The amount of catalyst to be added depends upon itscomposition and upon the type of reactants used. In general 1% to 9%,calculated for solid components of the reaction mixture, are sufiicient.Smaller amounts can, of course, also be used and the reaction proceedsalso without the addition of the catalyst. The reaction requires usually/2 hour to 4 hours to be completed. In some instances it may requiremore time or it may proceed in less than half an hour. After thereaction is completed, the final products are dried, preferably at 7080C. In order to characterize the new compounds, their total lead content,their reactive lead content, i.e. that portion of the lead content whichis capable of reacting with hydrochloric acid, their density, and their.free fatty acid content are determined. The free fatty acid contentserves also as an indication for the completeness of the reaction. Whenproceeding according to the methods given herein-above under (a) sub (1)to (5) and under (b) sub (1) and (2) the reaction is considered to becompleted as soon as the free fatty acid content has decreased to about1% or less.

When producing higher basic products, the reaction is considered to becompleted as soon as the yellow color of li-tharge has disappeared and aWhite product has been formed.

Of the basic lead sulfates to be used as starting materials, tetrabasiclead sulfate (4PbO.PbSO has proved to be the most suitable reactant dueto its high reactive' lead content. Lower basic lead sulfates, such as,for instance, tn'b-asic lead sulfate may also be used as startingmaterial. cording to known methods. They are directly converted into thebasic complex lead compounds according to the present invention withoutany further processing and purification after their preparation. Theformula of tetra-J basic lead sulfate 4PbO.PbSO leads one to assume thatthe 4 moles of lead oxide PbO are bound rather loosely and thus, arequite reactive. It was found that said 4 moles of lead oxide can bereacted with 1 mole to 8 moles of monobasic organic acid or with 1 moleto 4 moles of dibasic organic acid. For instance, when using stearicacid, compounds of the general formula n indicates the numerals 3.5 to Oand m the numerals 0.5 to 4.0,

are obtained.

Additional lead oxide can be incorporated into such compounds until thecoordination number 4 for lead sulfate and the coordination number 3 forlead stearate are completely occupied. The resulting compoundscorrespond to the following formula nPbO.PbSO .mPb(C H CO 2 wherein nindicates the numerals 4 to 16 and m the numerals 0.5 to 4.

(2PbO.PbHPO /2H O) as the inorganic reactant, it can be assumed that 2moles of lead oxide per each mole of lead phosphite are capable ofreacting with the organic acid. It follows that 4 moles of stearic acid'are bound. However, it has been found that moles of stearic acid can bereacted with 1 mole of basic lead phosphite. The reaction with the first4 moles of stearic acid proceeds rather rapidly and the resililtingproducts are characterized by the following formu a:

The basic lead sulfates are produced acwherein n'indicates the numerals1.5 to 0 and m the numerals 0.5 to 2.0.

The theory is advanced, although the invention is not limited to such atheory, that reaction of basic lead phosphite with 5 moles of stearicacid yields a compound of about the following composition:

Pb -2Pb(Ol7H35000)l Further amounts of lead oxide can also beincorporated into said product until the coordination number 2 of leadphosphite and the coordination number 3 of lead stearate are completelyoccupied.

When using basic lead carbon-ate (white lead) corresponding to theformula as the inorganic reaction component, it can be assumed that thegroup Pb(OH) is capable of reacting with 2 moles of stearic acid whenemploying stearic acid as 0rganic acid reactant. It has been found,however, that the reaction proceeds very smoothly until 4 moles ofstearic acid are consumed and that, in addition thereto, reaction with 5moles to 6 moles of stearic acid is possible. The speed of reaction isrelatively uniform until 4 moles of stearic acid are introduced into themolecule. For the introduction of 5 moles of stearic acid a longerreaction time is required, namely 12 hours and for the introduction of 6moles of stearic acid a reaction time of 30 hours was not evensufiicient to achieve complete reaction. The resulting products areillustrated by the following formulas:

It is evident that normal lead stearate is obtained when carrying outthe reaction to the end. Thus, a method of producing normal leadstearate from white lead and stearic acid has been made available by thepresent inventi-on.

It is, of course, also possible to introduce additional amounts of leadoxide into the intermediate products prepared from basic lead carbonateand stearic acid.

The following examples serve to illustrate the present inventionwithout, however, limiting the same thereto.

Exdmiple 1 3 g. of triethanolamine stearate are dissolved in 450 cc. ofwater. 54.4 g. of flaky stearic acid are added thereto at a temperatureof 55 C. 119.5 g. of tetrabasic lead sulfate are added portion byportion to the warm dispersion while stirring vigorously. The reactionmixture is stirred for 2 /2 hours. The resulting white product isfiltered off and dried at about C. 1

Tot-al'lead content: 60.2%

Content of lead capable of reacting with hydrochloric acid: 48.1%.

Example 2 PbSO L4Pb (C H COO 2 Density: 2.4.

Exdmple 3 3.5PbO.PbSO .0.5Pb(C H CQO) 2 119.5 g. of tetrabasic leadsulfate are dispersed in 400 cc. of water at room temperature whilestirring. 27.2 g. of oleic acid are added portion by portion to thedispersion at the same temperature. After half an hour the slightlyyellowish product is filtered oil and dried at about 70 C.

Total lead content: 71.0%

Content of lead capable of reacting with hydrochloric acid: 56.8%.

Density: 3.6.

Example 4 14.6 g. of adipic acid are added to a dispersion of 119.5 g.of tetrabasic lead sulfate in 400 cc. of water. The mixture is stirredat room temperature for half an hour. The resulting white product isfiltered oil and dried at about 80 C.

Total lead content: 77.8%.

Content of lead capable of reacting with hydrochloric acid: 62.3%.

Density: 3.4.

52.4 g. of flaky stearic acid are dispersed at C. in 700 cc. of waterwith the addition of 0.06 g. of sodium hydroxide while stirring. 74.3 g.of dibasic lead ph-osphite are added portion by portion to thedispersion. After half an hour the resulting white product is filteredoff and is dried at about C.

Total lead content: 48.9%

Density: 1.9.

Example 6 PbHPO .O.5I-I O.2Pb (C H COO 2 54.4 g. of molten stearic acidare slowly added at room temperature to a dispersion of 37.2 g. ofdibasic lead phosphite in 400 cc. of water while stirring. Stirring ofthe reaction mixture at 55 C. is continued for 5 /2 hours. The resultingwhite product is filtered off and dried at about 80 C.

Total lead content: 34.6%.

Density: 1.7.

Example 7 77.6 g. of basic lead carbonate are dispersed at roomtemperature in 400 cc. of water with the addition of 5 cc. ofpolyethylene glycol (molecular weight 50,000). The temperature isincreased to 55 C. and 27.2 g..of flaky stearic acid are added portionby portion to the dispersion. After 1 hour the white product is filtered01f and dried at about 80 C.

Total lead content: 59.8%

Density: 3.1.

In the following tables there are given a numberiof other basic complexlead salts prepared according to application Serial No. 629,461. Thesecompounds are prepared in the same manner as described hereinabove inthe examples whereby the amounts of inorganic basic lead salt, oforganic acid and, if desired, of lead oxide which are to be reacted, aregiven.

TABLE I-REACTION PRODUCTS OF TETRABASIG LEAD SULFATE (a) AND STEARICACID (b) Molar ratio oi- Example No. Formula oi Reaction Product DensityTotal lead, Reactive lead,

Percent Percent 1 1 3.5 PbO.PbSO4.0.5 Pb(Cl7H=5COO)a-.- 2. 6 71. 0 56. 81 2 3 PbO.PbSO4.Pb(C11H3sCOO)1 2. 4 60. 2 48. 1 1 3 2.5 PbO-PbSO4-L5Pb(C11H55COO),- 2.0 62.2 41. 7 1 4 2 PbO.PbSO4.2 Pb(C17Ha5COO)2 1. 8 46.2 36. 8 1 5 1.5 PbO PbSO4.2.5 Pb(Ci1Hs5COO)g 1. 5 41.3 33.0 i 6 PbOPbSO4.3 PD(CI7HMCOO 1.4 87.3 29.9 1 7 0.5 PbO.PbSO4.3.5 Pb(C11H; COO 1 434.3 27. 3 1 B PbSO A Pb (0111513 00 0), 1. 4 31. 4 25. 1

TABLE II-REACTION PRODUCTS 0F TETRABASIG LEAD SULFATE (B) AND VARIOUSACIDS (c-l) Molar ratio oi- Example No. Formula oi Reaction ProductDensity Total lead, Reactive lead,

Percent Percent (a) 1 3. 6 71. 0 56. 8 1 4. 0 71. 0 56.8 1 3. 7 77. 862. 3 1 3. 4 77. 8 62. 3 1 4. 9 79. 2 62. 5 1 3 PbO-PbSO4-PbC6H4(COO 4.4 76. 6 61. 3 1 3.5 PbO.PbSO4.0.5 PMC1313000) 3.7 74. 8 59. 8 1 PbSOoPb(CiiH23COO): 1. 5 38. O 30. 4

I The letters (c-i) as used in the preceding Table II indicate theiollowing acids: (0) =o1eic acid; (d)=linoleic acid; (e)=a-ethylhexanoic acid;

adipic acid; (g) =benzoic acid; (11) =phthalie acid; (l)=1aur1e acid.

TABLE III-REACTION PRODUCT F DIBASIC LEAD PHOSPHITE (1) AND STEARIC ACID(b) Molar ratio oi.- Example No. Formula oi Reaction Product DensityTotal lead,

Percent (i) 1 1 1.5 PbO.PbHPO5.0.5 H20.0.5 Pb(Cl7H36COO)2 2. 6 61. 8 1 2PbO.PbHPO3.U.5 H20.Pb(C17Ha5CO0)2 1. 9 48. 9 1 3 0.5 PbO-PbHPOz.O.5H1015 Pb(C1vH35OOO)2. 1. 8 40. 1 4 PbHPOa.0.5 1120.2 Pb(C17H35COO)3 1. 734. 6 1 5 PbHnPO3(C17H35COO).O.5 H .2 Pb(C17H35C0O)z 1. 6 30. 2

TABLE IVREACTION PRODUCT OF BASIC LEAD CARBONATE (k) AND STEARIC ACID(b) Molar ratio 01- I Example No. Formula oi Reaction Product DensityTotal lead,

percent TABLE V-REACTION PRODUCT OF TETRABASIC LEAD SULFATE (a), STEARICACID (1)), AND LEAD OXIDE (l) Molar ratio of- Example No. Formula oiReaction Product Density Total lead, Reactive percent lead, peri cent 11 1 4.5 PbO P135041) 5 Pb(C11Hz5COO)z. 3. 4 73. 9 61. 5 1 1 1. 5 '5 PbOPbSO4.0.5 Pb(C11Hz5C 3. 6 75.0 63. 5 1 1 2 5.5 PbO PbS04.0.5Pb(C11Ha5COO) 4. 3 76.1 65. 3 1 2 4 7 P PbSO4.Pb(C1-1H3 OOO), 3.1 71.463.4 1' 8 12 12 PbO.PbSO4.4 Pb(C11H;5C0O) 2. 0 58. 9 55. 4 1 8 13 13PbO.PbSO4.4 Pb (01 1 155000) 2.4 60. 0 56. 7 1 8 14 14 P PbSO4.4Emmi-111M000) 2. 5 61. 2 58. 0 l 8 15 15 PhD PbSOiA Pb(Cl7H35COO) 2. 662. 2 59.0 1 8 16 16 PbO.PbSOi.4 Pb(C17Ha5COQ) 2. 9 63. 2 60. 3 1 8 1212 PbO.PbSO4.4 Pb (011113000).-. 2. 6 64. 7 61.0

Laurie acid.

TABLE VI-REACTION PRODUCT OF ETRABASIC LEAD SULFATE (a), STEARIC ACID(b), ANOTHER ORGANIC ACID (0, g, h, and (m AND LEAD OXIDE (1) ExampleMolar ration of (c), (a), (b) (g), (h), Total lead, Reactive No. (m (e)Formula oi Reaction Product Density percent lead, percent 44 1 1. 5 0. 54 6.75 PbO.PbS0 0.75 Pb(C17H;5OO0);.0.5 PbCBH4 3.4 73. 2 65.0

45 1 1. 5 (1(5) (41) 7 llbodlbsomfi Pb(Ci7H85000)l.0.25 Pb(CtH 3. 6 73.5 65. 3

47 1 1. 5 0.5 4 7 PbO.PbSO .O.75 Pb(C1-/HCOO),.0.25 Pb(Cr7Hu- 3.1 71. 363. 4 (c) (1) COO).

1 The letter (In) used in the preceding Table VI indicates salicylicacid.

TABLE VII-REACTION PRODUCT OF DIBASIC LEAD PHOPHITE (j), STEARIC ACID(b), AND LEAD OXIDE (l) Molar ratio of- Reactive Example Formula oiReaction product Density Total lead, lead, per- No. percent cent 1 2 1 2PbO.PbHPO3.Pb(C11H35CO0):; 2. 2 54. 4 40. 7 1 2 2 3 PbO.PbHPO3.Pb(0111135600); 2. 4 59. 3 47. 4 1 2 3 4 Pb0.PbHP03.Pb(C17H35C OO)! 2.763. 2 52.6 1 2 4 5 PbO.PbHPOa.Pb(CnHuCOO): 2.9 66. 2 5o. 7 1 4 7 7PbO.PbHPOi.2 Pb(C17Hz5CO0)i 2. 9 61. 1 55. 0

TABLE VIIIr-REACTION PRODUCT OF BASIC LEAD CARBONATE (k), STEARIC ACIDAND LEAD OXIDE (1) Example No.

Molar ratio 01- Formula 01' Reaction Product Density Total lead, percenthumans-an In place of triethanolamine stearate used as catalyst inExample 1 or of sodium stearate used as catalyst in Example 5, or ofpolyethylene glycol used as catalyst in Example 7, there may be employedother catalysts which cause wetting of the react-ants, for instance,aliphatic monohyd-ric and polyhydric alcohols, such as isopropanol,glycerol; aromatic monohydric alcohols, such as benzyl alcohol;sulfonates of fatty alcohols.

As shown in Example 5, the catalyst may be formed in the reactionmixture by the addition of agents capable of combining with each otherto form the desired wetting agent.

Of course, many changes and variations in the reactants, the inorganicbasic lead salts, thev organic monoor dibasic acids, the catalyticallyacting wetting agent, in the reaction conditions, temperature, andduration, in the amounts of lead oxide added additionally to thereaction mixture, in the concentration and molar ratio of The startingmaterials of the test composition were taken from the same batch for alltest films. The test composition consisted of Parts Suspension polyvinylchloride, trademark Vestolit S 70 100 Dioctylphthalate, trademarkVestinol AH spez. 50 Stabilizer 2 INO R GANIC-O R GANIC LEAD COMPLEXESBeginning of End of lubri- Stab. of Molar ratio 01 starting matermlsLead Density discoloration eating action, 10 Ex. No. content to brown,minutes ohmscm minutes 4 Pb0.PbSO4:stearic acid=lz1 71 2. 6 45 27-35 7.8 4 llEbiOiPbsfiOrzlead oxidezstearic acidzbenzoici cid= 73. 5 3. 6 9037-42 6.6

.5:0. Dibasic lead phos hitezPbO :stearlc acid=1:3:2 64. 4 2. 7 90 40-453. 5

the reactants in the aqueous dispersions and/or solutions, We claim:

in the method of removing the resulting basic complex lead salts fromthe reaction mixture and of drying them, and the like may be made bythose skilled in the art in accordance with the principles set forthherein and in the claims annexed hereto.

The new basic complex lead salts according to the present invention havea remarkable stabilizing effect upon plastics of the polyvinyl chloridetype and of copolymerization products containing such polyvinylchlorides such as copolymerization products of vinyl chloride with vinylacetate, vinylidene chloride, acrylonitrile, vinyl propionate, vinylbutyrate, vinyl chloro acetate, ethyl met-hacrylate, and others.

The amount of stabilizing basic complex lead salts according to thepresent invention admixed to the plastic composition is preferablybetween about 0.5% by weight and about 10% by weight of the amount ofhalogen-containing plastic, and especially of polyvinyl chlorideemployed. Especially advantageous results are achieved when admixingbetween about 2% by Weight and about 3% by weight of the basic complexlead salt to the plastic composition.

The stabilizing effect of the new basic complex lead compounds accordingto the present invention is far superior to the stabilizing eifectachieved by other basic inorganic lead compounds as they areconventionally used as stabilizing agents. The stabilizing effect isespecially evident when testing the respective compositions for theirheat stability and their specific electrical resistivity.

The following examples show compositions according to the presentinvention as they are used for coating and painting, for making film'sand foils or plastic articles, and for other purposes without, however,being limited thereto.

the invention together with their stabilizing characteristics, theirlubricity and their specific electrical resistivity.

1. A surface coating composition comprising a film forming vehicleselected from the group consisting of a vinylchloride homopolymer andcopolymer and the complex lead compound of the formula nPbo.PbAc .mPb(Ac wherein n indicates the numerals 0 to 16;

m indicates the numerals 0.5 to 4;

Ac indicates the dibasic inorganic acid residue selected from the groupconsisting of the sulfate group the carbonate group CO and the phosphitegroup HPO3: r

Ac indicates an organic acid residue selected from the group consistingof the residue of a saturated monobasic aliphatic acid, an unsaturatedmonobasic aliphatic acid, a saturated dibasic aliphatic acid, anunsaturated dibasic aliphatic acid, a monobasic aromatic acid, and adibasic aromatic acid; and

x indicates the numeral 1 when Ac is the residue of a dibasic organicacid, and the numeral 2 when Ac is the residue of a monobasic organicacid,

plastic.

References Cited by the Examiner UNITED STATES PATENTS 3,072,693 1/ 1963Szczepanek 260-435 MORRIS LIEBMAN, Primary Examiner. ALEXANDER H.BRODMERKEL, Examiner. K. B. CLARKE, A. KOECKERT, Assistant Examiners.

1. A SURFACE COATING COMPOSITION COMPRISING A FILM FORMING VEHICLESELECTED FROM THE GROUP CONSISTING OF A VINYLCHLORIDE HOMOPOLYMER ANDCOPOLYMER AND THE COMPLEX LEAD COMPOUND OF THE FORMULANPBO.PBAC1.MPB(AC2)X WHEREIN